


the symbiosis between you and me

by deplore



Category: Hunter X Hunter
Genre: M/M
Language: English
Status: Completed
Published: 2014-12-29
Updated: 2014-12-29
Packaged: 2018-03-04 03:52:53
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,029
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2908394
Author URL: https://archiveofourown.org/users/deplore/pseuds/deplore
Summary: <blockquote class="userstuff">
              <p>Gon has a parasite growing in his body, but he's also the most content that he's ever been. Killua is, as always, selfless to a fault.</p>
            </blockquote>





	1. Chapter 1

“There’s a scary new rumor going around, have you guys heard it?” Leorio asks. Gon likes the way that Leorio talks with his own body – his hands go everywhere, he tilts his head back and forth and side to side, the look on his face is always ludicrously full of emotion – it’s hard not to get caught up in his pace when he’s bright and bold and right in your face, Gon thinks.

Killua, though, is immune to Leorio’s ways. He continues putting sugar cube after sugar cube into his coffee, barely even looking up. “Rumors are usually completely baseless, aren’t they?” he replies. “More often than not they’re completely wrong.”

“No, but this one is seriously scary!” Leorio says, undeterred. “And it might be true, it’s been going around Botanical Hunters and Virus Hunters lately. Apparently, there’s this plant that might’ve washed in from the Dark Continent that’s infecting people… people wake up with this dark spot right above their heart, and then over time it grows into this line, and the line spirals up and around until it finally reaches the back of the neck – and then the person dies. Creepy, isn’t it?”

Gon tilts his head. “Well, plants have to feed off of something, so I guess there could be one that feeds off of humans,” he says. “Like how ivy feeds off of whatever it grows on.”

“Nobody knows, though,” Killua says. He picks up a spoon and begins stirring, letting the spoon clatter noisily against the edges of the cup. “So what’s the point in even talking about it?”

Gon can tell Leorio is a bit put out by Killua’s reaction; he sets his hand on Killua’s shoulder gently. He’s tenser than Gon had expected. “By the way, Leorio, how’s Kurapika doing?” he asks, changing the subject. “I heard he’s been pretty active in the mafia lately, is he taking care of himself?”

“He’s finally started picking up his phone on a regular basis,” Leorio replies, readily eased into the new topic of conversation.

Gon can feel Killua relax a little, so he lets go and smiles.

 

* * *

 

 

It’s already been three days since Gon woke up and found a mark on the left side of his chest, and no matter how hard he scrubbed at it in the shower, it would not be washed off.  It’s already been over 72 hours since Gon sat down at an Internet cafe when Killua was occupied with other tasks, wondering if it might be a skin condition, and found instead strange rumors: “The spot will grow like a vine, all the way up and around your chest, and then when it gets to your neck, you die. I watched it happen to my friend. It’s real. The doctor she went to said it wasn’t a problem, but she died.” The same story, over and over again, until Gon found himself believing it was probably true.

It’s already been 4,320 minutes since Gon noticed the mark, and he’s realized that it really _is_ growing – this really might be his death sentence. It’s already been 259,200 seconds, most of which have been occupied by a single thought: _Killua can’t know about this._ Not until he’s figured out the right way to tell Killua properly.

After they finish their coffees, Gon and Killua walk back to the hotel they’ve booked for the week as they pass through Yorkshin City. “It was nice to see Leorio again, I’m glad he’s doing well,” Gon says conversationally. “He’s always got plenty to talk about, doesn’t he?”

“Yeah, he says a lot of words with not a lot of meaning to them,” he replies.

Gon looks up to take stock of the look in Killua’s eyes. “You’re kinda irritable today, aren’t you?” he asks, reaching to squeeze Killua’s hand discreetly, lightly drawing circles into Killua’s palm with the bad of his thumb.

Killua sighs almost imperceptibly, except that Gon’s got a read on all of Killua’s little tells. “I didn’t like the coffee that much, I guess,” he answers.

Gon can tell when he’s not going to get Killua to crack no matter how much he pesters, so he decides to let it go.

 

* * *

 

 

A week passes. The black mark begins to grow counterclockwise around his chest, and Gon begins to notice it takes just a little longer for him to shape his Nen, and there’s a weakness at his chest whenever he exerts himself – nothing enough to actually impede him, but enough that he can feel something pressing at his ribcage. He knows he can’t hide it from Killua forever, but he decides to keep quiet for as long as possible.

In the meanwhile, life goes on and Gon’s content to be swept along in its pace. They move onto another city to take a small-time job providing security for the transportation of a rare art collection – it’s easy work for a big paycheck, and it lets Gon keep his condition under wraps for the time being.

Even still, the collection gets attacked in transit and the two of them dispatch with twenty or so would-be thieves. For a few moments, in the heat of the confrontation, Gon feels a wrenching pain sear through his body as if his organs are being split from the inside out – he catches himself before he falls to his knees in the middle of the fight, but before he can collect himself, one of the attackers nearly slashes Gon’s face with a knife were it not for the fact that Killua grabs both his arms and pulls back until Gon can hear the audible _snap_ of bone. Gon flashes Killua a brief smile and thumbs-up. “Thanks, Killua,” he says.

Killua scoffs, but even after all these years, he still goes a little red at the ears. “If you want to thank me, don’t get distracted again,” he says, breathing a little heavier than usual. “It’s not like you to slip during a fight.”

The two of them leave the thieves a pile of broken men, politely dumped a few blocks from the hospital.

 

* * *

 

 

To make a long story short, Gon is content. His contentment is different from a temporary feeling of accomplishment, or the waxing and waning of happiness as an emotion – it’s a serene appreciation of what he has in life that permeates every bit of what makes him himself: his skin and his soul, his bones and his heart. Even if he were given anything else, he wouldn’t want for it. But if anything were taken away, then he would fall into discontent.

It is a state of being that requires both hard work and luck to attain. Sometimes, Gon wonders if he deserves it – especially having Killua at his side even after all the mistakes he made in his youth – but those doubts are easily assuaged, because the fact of the matter is, contentment does not go to those who deserve it most but to those who are most accepting of it. People who always desire more will never achieve it, but Gon’s desires in life are few.

People he can call his friends. A place to go back to that he can call home no matter how long he’s been gone from it. A world to be explored. The knowledge that there is always somewhere that the sun is rising. Killua, who watches his back and lets Gon watch his own in turn. Those are all the things he’s ever needed for.

 

* * *

 

 

Gon’s secret is exposed like this: the day after their job is over, they’re on the hotel bed kissing and Killua has Gon pinned down while he pulls at the hem of Gon’s shirt. “Wait, let me take yours off first,” Gon says, pushing at Killua’s arms, but it’s too late – the black line is already exposed.

Killua’s fingers trace it before stilling at where it begins, over Gon’s heart, where the mark is darkest and heaviest. “How long?” Killua asks.

“Almost two weeks,” Gon admits, because there’s no point in lying. “I thought you didn’t believe in rumors.”

“Yeah, but I’d believe in you,” Killua replies sharply. Gon doesn’t have a counter for that, so for a few moments, they simply sit and stare at each other in silence. Gon can tell that Killua is mentally evaluating what to say next. _Why didn’t you tell me_ , maybe, or _How long were you going to keep this a secret?_

Instead, though, Killua just sighs wearily and rests his forehead against Gon’s shoulder. “I’ll do whatever I can,” he murmurs. (The tone makes Gon think of the first time Killua said _I love you_ – it’d been right after they’d escaped near-certain death after accidentally falling into a trap, and Killua had confessed it all quiet and shy and genuine and sounding a little afraid he’d never have a chance to say it in the future – it was the same tone he’s using now.)

Gon knows he shouldn’t, but he smiles despite himself before reaching out to hug Killua, resting his head against Killua’s. “Come on, it’ll take way more than this for you to finally get rid of me,” he says, voice a little muffled.

“Yeah, I know,” Killua replies, and Gon laughs.

 

* * *

 

 

The nice thing about being Hunters is that there’s very little that ties them down to one particular place beyond what they choose to tie themselves to, so they take off by train to a seaside town called Outset Bay the next day on Killua’s suggestion, booking a sleeper car to themselves. Gon knows Killua wouldn’t admit it, but he suspects that Killua picks the town because the scenery reminds him a little bit of Whale Island. Their overnight goes smoothly – even though there’s two beds in the car and it’s a tight enough squeeze with each of them in their own, they sleep with Gon’s chest pressed up against Killua’s back. The extra pressure means that he can feel the roots of the plant above his heart whenever he inhales, but he keeps Killua pulled up close anyway.

When they arrive at Outset Bay, they rent out a cottage with a nice view of the shore. “I passed through here with Alluka once,” Killua says as they stand in front of the living room window, admiring the scenery.

“Yeah?” Gon replies. He can sense there’s something else that Killua is building up to, so he decides to settle for idle chitchat until Killua’s ready. “I bet she enjoyed it a lot.”

“She prefers mountains over the beaches,” Killua says. He sighs sharply and adamantly keeps his face fixed forward as he continues. “I called her before we left to see if she could help. She says that she’s seen a case of this before, and… whatever the plant is, it probably comes from the same place that her powers come from, because her powers don’t work on it like they should.” He crosses his arms. “Besides, even if she could, it wouldn’t be healing. It’d be destroying the plant.”

In the distance, there’s a ship coming in to dock. Clouds float lazily across the sky, and in the silence of the room, Gon can hear the sound of the waves crashing onto the shore. He smiles. “I like the view from here than the one in the bedroom,” he says. “Let’s move the bed here.”

Finally, Killua turns to meet Gon’s gaze before he nods and offers a tiny smile in return.

 

* * *

 

 

They keep abreast of the rumors by using the Hunters-only website, where information about the plant percolates slowly. It’s a parasite, most likely a specimen from the Dark Continent. It feeds off of Nen, and so only affects those who are able to use it. Nen exorcism has no effect upon it. Those who can use manipulation or transmutation can stave off the growth of the plant if their abilities are potent enough; otherwise, the plant will just absorb the Nen. It runs its course in about four or five weeks. Botanical Hunters come to the conclusion that in the meanwhile, lacking a way to kill off the parasite, the best thing to do is to ease the victim’s suffering as the plant spreads itself through the body.

The plant itself is just as much a topic of interest as the treatment of its infection. For almost a whole 24 hours, the top post on the website is about it:

> Here’s something interesting I heard. I don’t know if it’s true or not. Apparently, in the late stages of the infection, the parasite buries itself through the brain stem as it pushes through the back of the neck, and a bloom sprouts inside the mouth. It continues to feed off of the host even after the host has died, until it has exhausted the corpse of its nutrients.
> 
> But it seems the parasites can’t coexist, and that might be the key. If the flowering parasite comes into contact with another parasite, they’ll both try to cannibalize the other and both will die – they are not unlike human beings in that regard, I suppose.
> 
> Posted by: hedera helix

After a while, they decide to stop looking at the website altogether without ever conferring in words. It’s a spontaneous simultaneity – they glance at each other after reading the post and instinctively understand: _it’s pointless, let’s stop this_.

So they do.

 

* * *

 

 

Gon and Killua were 18 when they reunited, over three years since they’d parted ways. They could’ve met up earlier, because Killua had left Alluka in the care of a Nen exorcist to teach her more about her powers a year before Gon got into contact with him, but Gon hadn’t been ready yet. He’d waited until the day that he could think to himself, _I’ve managed to become somebody Kite could be proud of_. Then Gon called Killua and Leorio and Kurapika to meet up in Zaban City at the cedar tree on top of the hill, and just like that, the pieces clicked back together perfectly in place. Killua became his traveling companion again.

Gon had just turned 19 when he realized that he loved Killua in a way that was a little deeper than the kind of love best friends have, and he’d blurted it out almost exactly the moment he had this epiphany – which, incidentally, was also when they were in the middle of a fight and he’d watched Killua narrowly avoid getting stabbed straight through the heart. “Killua, I’m in love with you,” he’d said, and then promptly knocked one of their enemies unconscious.

Killua had blushed and nearly missed the person he’d thrown a punch at. “You moron, can you not read the atmosphere, this is _not_ the time or the place,” he’d snapped, so Gon had let it drop.

Two months later, on a different job, they’d literally fallen into a trap and barely managed to save themselves from being skewered to pieces by spikes from below. “Gon, I love you,” Killua said quietly, but the softness of his voice couldn’t conceal the depth of emotion in his tone, like he wasn’t sure if he was more scared he’d never get a chance to say it again or more scared of being in love.

They were 20 when they had sex for the first time and Gon could sense that Killua had finally come to ease with revealing all of the vulnerabilities that come with being in love. It’s one of the things that Gon is sure that he’ll never forget – entwining his fingers with Killua’s, the desire to be close so intense that it felt almost as if their bodies were in the way, and after they’d exhausted each other, Gon had made Killua a promise: “As long as you still want me by your side, I’ll make sure you’re never alone. I promise,” he’d said.

Killua had smiled. “You'd better not go back on that,” he'd replied.

 

* * *

 

 

By the fourth day they spend in Outset Bay, the plant spreads a full ring across Gon’s collarbones and begins crawling up his neck. Gon can feel it eating away not only at his aura but also his body, sucking away the nutrients from the food he eats, consuming his muscles and bones for protein and calcium. It’s late fall, but whenever he goes outside with Killua, the wind sends terrible chills down his spine; even indoors, he wears layer upon layer to keep warm and hide the plant’s marking from view.

Neither of them ever mastered cooking beyond the art of boiling eggs and toasting bread, so they buy pre-packaged meals from the nearest grocery and order monstrous amounts of take-out from all of the restaurants within walking distance.

At dinner that night, Gon looks up from his carton of stir-fried noodles and notices that Killua’s sweater hangs a little loose on his shoulders. “Killua, you’re getting skinnier,” he says, “it’s because I’m eating everything, I bet. I’m sorry – ”

“Don’t ever say you’re sorry for something like this,” Killua cuts in.

Gon looks up, surprised. Killua does not meet his eyes. “You’re right,” Gon relents. “I won’t do it again.”

“Good,” Killua replies, though he sounds somewhat defeated. 

 

* * *

 

 

Death slowly sinks into Gon’s veins, but from it he feels a sense of clarity that he’s never experienced before. It’s the same calm and dangerous presence of mind that makes him a vicious fighter when his back’s to the wall and the odds aren’t in his favor, like he can instinctively predict everything that’s going to come to pass, except as a state of mind rather than fleeting moments of intense lucidity. Most likely, he’ll die quietly in his sleep, so he starts wrapping Killua’s arm over his waist instead of the other way around, so that Killua won’t wake up to find a dead man clinging to him. But he isn’t scared of dying – Gon Freecss is a Hunter, after all – he’s been ready to die at any moment ever since he decided to take the Hunter Examination.

He writes a letter and seals it with Nen that will undo when he dies, hiding it somewhere that he knows Killua will find before leaving the seaside cottage. In it, he writes only two sentences:

> _Tell everyone I went to explore and I don’t know when I’ll be back. I’m sorry for breaking our promise._

Gon knows that this letter is, in 20 words, why Killua never wanted to fall in love: sometimes love is beautifully selfish – sometimes love is choosing what hurts less.

 

* * *

 

 

They spend most of their time just relishing in each others’ beings, spending every moment together as if there were invisible chains linking them wrist to wrist, ankle to ankle, heart to heart. They walk up and down the shore until their feet have touched every grain of salt on the beach. They touch each other almost constantly, holding hands everywhere they go and holding each other in even closer ways when they’re alone with each other.

Eventually, the plant roots itself so firmly that Gon doesn’t have the energy to go outside for long. He spends hours lying against Killua’s chest, or with Killua resting his head in his lap. They don’t talk much, but when they do, they don’t talk about the past. In a way, it’s the purest way of living – eschewing the past and forsaking the future, he can live fully in each present moment.

Like that, Gon could remain content were it not for the fact that he can tell Killua wouldn’t be able to share in it. He can see it in the dark circles underneath Killua’s eyes, in the way that Killua walks as if dragging an immense weight behind him, in every time Killua bites his lip as if holding something back. Gon knows that, in many ways, this is harder on Killua than it is on him.

One late evening the two of them lie against each other swaddled in blankets, and Killua reaches out to cup either side of Gon’s face. Gon smiles and puts his hands over Killua’s. “Hey, Killua,” he says, quiet even though it’s only the two of them. “You can tell me anything, you know? That’s one thing that’ll never change, no matter what.”

 “I’m not ready to tell you yet,” Killua says. He slips out of Gon’s hold and pulls the layers covering up his neck to reveal the insidiously dark lines of the parasite growing underneath his skin. Judging by how fast it’s been growing, Gon figures he has at least one more day, but after that, he doesn’t know and he doesn’t care to think about it.

Even still, he smiles and replies, “I’ll wait.”

Killua begins tracing the lines with his fingers softly. “Idiot. You can’t wait,” he says, without any bite in his tone.

“No, I can,” Gon says. “I’ve decided. Tomorrow is going to last forever, so I can wait as long as you need until you’re ready.”

“Why are you so selfish?” Killua asks, sounding almost as if the spirals growing around Gon’s neck are choking him. “Tomorrow’s not going to last forever, so don’t say stuff like that.”

Gon takes Killua’s hand and presses it against his chest before putting his own palm flat against Killua’s. Their hearts don’t beat in synchrony; the rhythms counterpoint each other. “It’ll be forever here,” he says. “And I’ve always been selfish with you, I can’t be changed at this point.”

There’s a pause, but then Killua smiles tightly. “And I always play along, so I guess I can’t be changed either,” he says, more tenderly than anything else. “Fine. Tomorrow will be forever. But I’ll tell you before forever ends, alright?”

Gon pulls Killua’s hand in and presses his lips to the knuckles before pulling Killua in for a kiss proper. For the rest of the night, they let the touch of their mouths and their hands say all of the things that they can’t put into words.

 

* * *

 

 

Tomorrow morning, Gon will wake up and burn the letter. He’ll let Killua go and make sure that Killua has let him go too. Tomorrow, Gon will unchain Killua from the present and give Killua the space in his heart for contentment in the future. It’s the last thing that he can do, the only thing that he can do to begin to make up for all of what Killua’s given him.

Tonight, though, he begs: let me have one more night to be selfish. Let me hold him. Let me kiss him. Let him be mine for a few seconds more. I’ll give Killua the future he deserves, so let me have the present. Tonight, one last time – let me be content.

**Notes for the Chapter:**

> At this point, this fic is both complete and incomplete. You can choose to continue reading, but if you're fine with this ending, then it may be best to stop here.


	2. Chapter 2

When Gon wakes up, the first thing he does is glance over to Killua. He has to get rid of the letter before Killua wakes up in turn – but before he can even move from the bed, he freezes.  

There is a vague _something_ in the depths of Killua’s mouth, a strangely-shaped flower with too many petals in a shade of pale violet that almost matches Killua’s hair. Gon can’t be sure if it’s just his imagination, but it seems to move slightly in the early morning light. He reaches out to shake Killua’s shoulder, but Killua won’t wake – Killua’s not breathing.

Killua’s not alive.

Gon pulls away the blankets and pulls down collar the high-necked shirt. There are dark circles winding around Killua’s neck, and Gon doesn’t know if the sound that he makes is a laugh or a sob.

There’s a piece of paper in Killua’s hands. Gon opens it to find two sentences – the words are shaky, but the handwriting is unmistakably Killua’s:

> _You promised I’d never be alone as long as I wanted you by my side. You don’t have to follow._

The letter is, in 20 words, why Gon has never been afraid of falling in love with Killua – his love is beautifully selfless. His love lets Gon choose what hurts less: living in the past on a broken promise, or giving up the future.

Gon smiles. The choice is easy.

**Notes for the Chapter:**

> The conceit of this fic is inspired/copped from [Breakfast](http://www.mangahere.co/manga/shokubutsu_zukan/c001/) by Mizushiro Setona. However, I was going for a different atmosphere/theme than Breakfast, so I hope that this fic stands on its own despite sharing the same conceit. 
> 
> If you've made it this far, I'm a little curious: what choice do you think was made?


End file.
